I know there are 1,000 ways to dull polished aluminum. The problem is keeping it polished. But still, I'm asking for ideas for fun's sake as much as maybe finding that perfect method.
I like dulled aluminum accessories, just like I like patina. It doesn't bother me that my slots aren't polished out, neither is my truck. The vibe is "this is how it's always been".
I just bought a used unpolished finned cover for the Dana 60 and am about to order an new polished one for the 44. I'm waiting till the one shows up to see the finish, but I think it's just dull. If it's burnished, I'll glass bead the new one.
I guess any kind of acid will dull. How about vinegar? I had a pair of those wrinkle black M/T valve covers. I used paint stripper to bring them down to raw aluminum. One had been polished and the other wasn't. The stripper dulled it some, but not all that much. I guess once the polish is gone it will slowly get "texture".
Here is the desired finish: